Generally, a toilet can be divided broadly into a flush type in which excrement is flushed down a drain with water, and a vault type in which excrement is stored in a tank. In the case of a flush toilet, excrement is flushed down a drain with water, and treated at a sewage-treatment plant. On the other hand, in the case of a vault toilet, excrement is drawn up from a tank by a vacuum car and the like, and carried to a sewage-treatment plant and treated.
In the sewage-treatment plant, sewage including excrement is stored in a septic tank, wherein organic matters in the excrement is decomposed and removed by effects of microorganisms such as activated sludge, and subsequently water is purified through several steps of treatment processes and discharged into river.
However, at the time of long time power failure and water failure by disaster such as earthquake, a toilet cannot be used, and excrement is pooled in large quantities in homes. From large quantities of excrement pooled, malodor is exhaled continuously, and living environment is considerably deteriorated by bad odor if excrement is left as they are. Accordingly, generally employed is a method in which excrement is put into a bag made of plastic, and stored in the sealing state for the time being. However, the method has a problem such that the bag made of plastic is easily damaged; it is damaged during the storing, excrement is leaked out, and malodor is exhaled to the surroundings. In addition, the method also has a problem such that the excrement put into the bag made of plastic are decayed as time goes and odorous gas is pooled, and the gas is leaked out from the bag made of plastic due to the pressure of the gas.
In addition, a simple toilet is used at a place such as a construction site, an event site, a campsite. However, a conventional simple toilet has a problem such that an excess quantity of excrement may be pooled in the toilet, and malodor is exhaled to the surroundings.
Under such circumstances, a highly water absorptive polymer for excretion treatment is disclosed, wherein an aqueous solution of an acrylic acid monomer having 50 mol % or more of the neutralization index is subjected to a polymerization reaction, a hydrophilic polyvalent epoxy compound and a polymerization initiator are added, and then a gelatinous solid body is formed by being subjected to a re-polymerization reaction by irradiating with light; moreover, the gelatinous solid body is dried with hot wind, crushed and sorted, then crushed materials are surface-treated by adding a surface crosslinking agent (Japanese Patent Application Laid-Open No. 2008-095016).